On March 13, 2024, Merck Sharp & Dohme, LLC (“Merck”) filed four additional IPRs challenging The Johns Hopkins University (“JHU”) patents covering methods of treatment using pembrolizumab, which Merck sells under the trade name Keytruda®.  These follow four IPRs filed by Merck on March 4, 2024 that we previously reported (see Merck Files Four IPRs Challenging The Johns Hopkins University Pembrolizumab Patents, March 12, 2024).  The new IPRs are IPR2024-00647 challenging U.S. Patent No. 11,649,287; IPR2024-00648 challenging U.S. Patent No. 11,643,462; IPR2024-00649 challenging U.S. Patent No. 11,629,187; and IPR2024-00650 challenging U.S. Patent No. 11,634,491 as being anticipated by and obvious over the prior art.

Similar to the March 4th IPRs, the new IPRs also challenge patents that are involved in an ongoing lawsuit filed by Merck against JHU in November 2022 (1:22-cv-03059 (D. Md.)).  Merck has now filed IPRs on all of the patents involved in that litigation.  The litigation remains ongoing and the IPRs are awaiting Institution Decisions.

Keytruda® was the world’s top selling drug in 2023, with $25 billion in world-wide sales.

We continue to monitor the Keytruda® IPRs and litigation and will provide updates as they become available.  For more information about these and other biosimilar and biologic drug patent disputes, visit BiologicsHQ.



The author would like to thank April Breyer Menon for her contributions to this article.


    Information contained in the Venable BiologicsHQ database relates to FDA-approved drug products listed in the CDER Purple Book or on the FDA website ( Information relating to FDA licensed products, FDA-approved indications, and aBLA and 505(b)(2) applications is obtained from public sources including the U.S. FDA website ( Information relating to litigations is given only for cases active from January 31, 2010 onward. Information relating to foreign biosimilar / biologics follow-on products approved in Australia, Canada, the E.U., Japan and South Korea is from public sources. Statistics graphics are compiled from information contained in the Venable BiologicsHQ database.


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